Method, computer readable medium and system for automated design of controllable oscillator

ABSTRACT

An method, a computer readable medium and a system for an automated design of a controllable oscillator are provided, wherein the method includes: receiving a set of input data through an automated design procedure, wherein the set of input data includes an initial circuit description file and a criteria file, and the initial circuit description file records initial values of parameters of one or more components within the controllable oscillator; performing simulation according to the set of input data through the automated design procedure to generate a simulation result; and selectively modifying at least one parameter within the parameters of the one or more components according to the simulation result through the automated design procedure. In addition, in the process of modifying the at least one parameter, connection relationships of all components within the controllable oscillator are unchanged.

BACKGROUND OF THE INVENTION 1. Field of the Invention

The present invention is related to automated circuit design, and moreparticularly, a method, a computer readable medium and a system (e.g. anautomatic design system) for an automated design of a controllableoscillator.

2. Description of the Prior Art

In a phase-locked loop (PLL), performance of a voltage controlledoscillator (VCO) is critical. In order to optimize the performance ofthe VCO, a circuit design engineer typically needs to spend time onmodifying parameters within the VCO, e.g. the number of stages ofinverter used in the VCO. For a purpose of reducing the time for circuitdesign, the automated design becomes more likely to be applied incircuit design. Many automated design methods of the related art is hardto be realized, however. For example, variables are too many to convergefor producing a clear result in practice. Thus, there is a need for anovel automated design method and an associated system, in order toreduce time for circuit design in practice.

SUMMARY OF THE INVENTION

An objective of the present invention is to provide a method (e.g. anautomated design method), a computer readable medium and a system (e.g.an automated design system) for an automated design of a controllableoscillator, in order to save time for circuit design without introducingany side effect or in a way that is less likely to introduce sideeffects.

At least one embodiment of the present invention provides a method foran automated design of a controllable oscillator. The method comprises:receiving a set of input data through an automated design procedure,wherein the set of input data comprises an initial circuit descriptionfile and a criteria file, and the initial circuit description filerecords initial values of parameters of one or more components withinthe controllable oscillator; performing simulation according to the setof input data through the automated design procedure to generate asimulation result; and in response to the simulation result not reachinga predetermined specification described by the criteria file,iteratively modifying at least one parameter within the parameters ofthe one or more components according to the criteria file through theautomated design procedure to generate an updated circuit descriptionfile, and performing simulation according to the updated circuitdescription file to re-generate the simulation result, until thesimulation result reaches the predetermined specification. In addition,in the process of iteratively modifying the at least one parameter,connection relationships of all components within the controllableoscillator are unchanged.

At least one embodiment of the present invention provides an automateddesign system for a controllable oscillator, wherein the automateddesign system comprises a storage device and a processing circuitcoupled to the storage device. The storage device may be configured tostore a set of input data and a program code corresponding to anautomated design procedure, wherein the set of input data comprises aninitial circuit description file and a criteria file, and the initialcircuit description file records initial values of parameters of one ormore components within the controllable oscillator. In addition, theprocessing circuit may be configured to execute the program code tocontrol the automatic design system to perform the automated designprocedure. In the automated design procedure, the automated designsystem performs simulation according to the set of input data togenerate a simulation result; and in response to the simulation resultnot reaching a predetermined specification described by the criteriafile, the automated design system iteratively modifies at least oneparameter within the parameters of the one or more components accordingto the criteria file to generate an updated circuit description file,and performs simulation according to the updated circuit descriptionfile to re-generate the simulation result, until the simulation resultreaches the predetermined specification. In addition, in the process ofiteratively modifying the at least one parameter, connectionrelationships of all components within the controllable oscillator areunchanged.

At least one embodiment of the present invention provides a method foran automated design of a controllable oscillator. The method comprises:receiving a set of input data through an automated design procedure,wherein the set of input data comprises an initial circuit descriptionfile and a criteria file, and the initial circuit description filerecords initial values of parameters of one or more components withinthe controllable oscillator; performing simulation according to the setof input data through the automated design procedure to generate asimulation result; and selectively modifying at least one parameterwithin the parameters of the one or more components according to thesimulation result through the automated design procedure. In addition,in the automated design procedure for the controllable oscillator,circuit architecture of the controllable oscillator is unchanged.

At least one embodiment of the present invention provides a computerreadable medium for an automated design of a controllable oscillator,wherein the computer readable medium stores a program code correspondingto an automated design procedure, and the program code is capable ofbeing loaded into a computer in order to execute the followingoperations: receiving a set of input data, wherein the set of input datacomprises an initial circuit description file and a criteria file, andthe initial circuit description file records initial values ofparameters of one or more components within the controllable oscillator;performing simulation according to the set of input data to generate asimulation result; and in response to the simulation result not reachinga predetermined specification described by the criteria file,iteratively modifying at least one parameter within the parameters ofthe one or more components according to the criteria file to generate anupdated circuit description file, and performing simulation according tothe updated circuit description file to re-generate the simulationresult, until the simulation result reaches the predeterminedspecification. In addition, in the process of iteratively modifying theat least one parameter, connection relationships of all componentswithin the controllable oscillator are unchanged.

The method, the computer readable medium storing the program code, andthe automated design system provided by embodiments of the presentinvention can perform iterative modification and simulation verificationregarding an oscillator with fixed architecture (e.g. connectionrelationships of components within the oscillator are unchanged), tofind at least one set of parameters of the components, making theoscillator conform to predetermined requirement or specification.

These and other objectives of the present invention will no doubt becomeobvious to those of ordinary skill in the art after reading thefollowing detailed description of the preferred embodiment that isillustrated in the various figures and drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram illustrating an automated design system according toan embodiment of the present invention.

FIG. 2 is a diagram illustrating a voltage controlled oscillatoraccording to an embodiment of the present invention.

FIG. 3 is a working flow of a method for an automated design of acontrollable oscillator according to an embodiment of the presentinvention.

FIG. 4 is a working flow of a method for an automated design of acontrollable oscillator according to another embodiment of the presentinvention.

DETAILED DESCRIPTION

Certain terms are used throughout the following description and claims,which refer to particular components. As one skilled in the art willappreciate, electronic equipment manufacturers may refer to a componentby different names. This document does not intend to distinguish betweencomponents that differ in name but not in function. In the followingdescription and in the claims, the terms “include” and “comprise” areused in an open-ended fashion, and thus should be interpreted to mean“include, but not limited to . . . ”. Also, the term “couple” isintended to mean either an indirect or direct electrical connection.Accordingly, if one device is coupled to another device, that connectionmay be through a direct electrical connection, or through an indirectelectrical connection via other devices and connections.

FIG. 1 is a diagram illustrating an automated design system 10 accordingto an embodiment of the present invention. The automated design system10 may comprise a storage device such as a storage system 120 and aprocessing circuit 140 coupled to the storage system 120. In thisembodiment, the storage system 120 may be configured to store a set ofinput data 120D and an automated design computer program product such asa program code 120C corresponding to an automated design procedure, andthe processing circuit 140 may be configured to execute the program code120C to control the automated design system 10 to perform the automateddesign procedure to perform an automated design of a controllableoscillator, wherein examples of the automated design system 10 mayinclude, but are not limited to: a personal computer, a server or anytype of computer equipment, and examples of the controllable oscillatormay include, but are not limited to: a voltage controlled oscillator(VCO), a current controlled oscillator or any type of oscillator. Inaddition, a storage system 120 may be a volatile memory or anon-volatile memory.

FIG. 2 is a diagram illustrating a VCO 20 according to an embodiment ofthe present invention. The VCO 20 may comprise a voltage controlledcurrent source (e.g. a transistor 220) and a buffer circuit 240 coupledto the voltage controlled current source. In this embodiment, the buffercircuit 240 may comprise a buffer chain circuit formed by a plurality ofbuffer units connected in series, e.g. a ring chain circuit formed byfive inverters {241, 242, 243, 244, 245} connected in series, where theinverters {241, 242, 243, 244, 245} are coupled to the transistor 220via a node Vring, but the present invention is not limited thereto. Inaddition, as shown in FIG. 2, the transistor 220 is further coupled to asupply voltage terminal VDD and a control terminal Vctrl, and an outputterminal of the inverter 245 is coupled to an output terminal VCO OUT ofthe VCO 20; thus, the VCO 20 may output a periodic signal having acorresponding oscillation frequency from the output terminal VCO OUTaccording to a voltage level on the control terminal Vctrl.

FIG. 3 is a working flow (e.g. an automated design procedure) of amethod (e.g. an automated design method) for an automated design of acontrollable oscillator (e.g. the VCO 20 shown in FIG. 2) according toan embodiment of the present invention. It should be noted that theworking flow shown in FIG. 3 is for illustrative purposes only, and isnot a limitation of the present invention, where one or more steps maybe added, deleted or modified in the working flow. In addition, if asame result may be obtained, these steps do not have to be executed inthe exact order shown in FIG. 3.

In Step 310, the automated design system 10 may receive a set of inputdata (e.g. the input data 120D), and store the set of input data in thestorage system 120. In this embodiment, the input data 120D may comprisean initial circuit description file and a criteria file, where theinitial description file records initial values of parameters of one ormore components within the VCO 20, e.g. an initial size of thetransistor 220, initial sizes of transistors within the inverters {241,242, 243, 244, 245}, and/or a voltage level of at least one node (e.g.the node Vring) within the VCO 20 under a condition of the initial sizesof the aforementioned transistors.

In Step 320, the automated design system 10 may generate a simulationresult (e.g. a tuning range of an oscillation frequency of the VCO 20,phase noise of the VCO 20, or power consumption of the VCO 20) byperforming simulation according to the set of input data (e.g. the inputdata 120D such as the initial circuit description file).

In Step 330, the automated design system 10 may determine whether thesimulation result reaches a predetermined specification described by thecriteria file, e.g. whether the tuning range conforms to a predeterminedrange value, whether the phase noise is less than a predetermined noisevalue, whether the power consumption is less than a predetermined powerconsumption value, and/or whether the voltage level on the node Vringexceeds an allowable voltage range (e.g. whether the voltage level onthe node Vring is greater than an upper bound thereof, where the upperbound may be defined based on an allowable highest voltage for thetransistors within the inverters {241, 242, 243, 244, 245}). If thesimulation result reaches the predetermined specification (e.g. thetuning range conforms to the predetermined range value, the phase noiseis less than the predetermined noise value, the power consumption isless than the predetermined power consumption value, and/or the voltagelevel on the node Vring does not exceed the allowable voltage range),the automated design procedure enters Step 370 and ends; if thesimulation result does not reach the predetermined specification (e.g.the tuning range does not conform to the predetermined range value, thephase noise is greater than the predetermined noise value, the powerconsumption is greater than the predetermined power consumption value,and/or the voltage level on the node Vring exceeds the allowable voltagerange), the automated design procedure enters Step 340.

In Step 340, the automated design system 10 may determine whether aniteration count within the automated design procedure reaches apredetermined count. If yes, the automated design procedure enters Step370 and ends; otherwise, the automated design procedure enters Step 350.

In Step 350, in response to the simulation result not reaching thepredetermined specification described by the criteria file, theautomated design system 10 may modify at least one parameter within theparameters of the one or more components according to the criteria fileto generate an updated circuit description file. For example, theautomated design system 10 may modify sizes of one or more transistorswithin the VCO 20 (e.g. increase/reduce the size of the transistor 220,and/or increase/reduce the sizes of the transistors within the inverters{241, 242, 243, 244, 245}) according to the criteria file.

In Step 360, the automated design system 10 may re-generate thesimulation result by performing simulation according to the updatedcircuit description file, and return to Step 330 to determine whetherthe simulation result reaches the predetermined specification aftermodifying the parameters within the VCO 20.

In Step 370, the automated design system 10 may end the automated designprocedure. For example, when the automated design procedure enters Step370 from Step 330, it means the automated design system 10 has made theparameters converge to a set of sizes that is applicable to thetransistors within the VCO 20 to reach the predetermined specification;in another example, when the automated design procedure enters Step 370from Step 340, it means that, before reaching the predetermined count ofiterations, the automated design system 10 cannot make the parametersconverge to a set of sizes that is applicable to the transistors withinthe VCO 20 to reach the predetermined specification.

In this embodiment, the criteria file may record one or more limitationconditions of modifying the at least one parameter, and the one or morelimitation conditions may comprise a parameter range of the at least oneparameter. More particularly, the parameter range of the at least oneparameter may comprise a size range of at least one transistor withinthe VCO 20. For example, the criteria file may record size ranges ofrespective transistors within the VCO 20, respectively, to prevent thesizes of transistors from converging to sizes that are hard to beimplemented and thus introduce additional costs during iterativemodification; in another example, the criteria file may record atransistor size range to make transistor sizes of all transistors withinthe VCO 20 be limited within the transistor size range; but the presentinvention is not limited thereto.

In some embodiments, the automated design system 10 may directly takeparameters (e.g. the sizes of transistors within the VOC 20) that arecurrently utilized for simulation as final parameters of the VCO 20 inresponse to the aforementioned condition where the iteration countreaches the predetermined count, but the present invention is notlimited thereto. In some embodiments, the automated design system 10 mayadaptively modify the one or more limitation conditions within thecriteria file in response to the aforementioned condition where theiteration count reaches the predetermined count, and redo the automateddesign procedure, but the present invention is not limited thereto. Inaddition, the automated design system 10 may apply modificationregarding any inverter within the buffer circuit 240 to other inverterswithin the buffer circuit 240, concurrently, in order to guarantee theinverters {241, 242, 243, 244, 245} remain identical to one anotherduring the modification.

In addition, the criteria file may record a modification mechanism toallow the automated design system 10 to be able to modify differenttransistors in response to different simulation results, or performdifferent modification on a certain transistor in response to differentsimulation results. Since those skilled in the art of customized designof a controllable oscillator can understand related details of how toestablish the modification mechanism in the criteria file, furtherdescription is therefore omitted for brevity.

Through the automated design procedure shown in FIG. 3, in response tothe simulation result not reaching the predetermined specificationdescribed by the criteria file, the automated design system 10 caniteratively modify at least one parameter within the parameter of theone or more components according to the criteria file to generate theupdated circuit description file, and re-generate the simulation resultby performing simulation according to the updated circuit descriptionfile, until the simulation result reaches the predeterminedspecification (or until the iteration count reaches the predeterminedcount). According to embodiments of the present invention, the automateddesign system 10 may determine whether to redo the iterativemodification and simulation according to a current accumulated iterationcount, where if the current accumulated iteration count has exceeded thepredetermined count, the automated design system 10 may end theautomated design procedure to avoid wasting additional time cost. Itshould be noted that, in the process of modifying the at least oneparameter, connection relationships of all components within the VCO 20are unchanged. That is, the automated design method of the presentinvention is performed under a condition where the circuit architectureis fixed (e.g. the number of stages of inverters is fixed). As a result,unnecessary variables can be reduced, which makes the automated circuitdesign of the VCO 20 be able to be implemented easily, and reduces timefor overall automated design procedure. In some embodiments, a voltagelevel of the control terminal Vctrl and/or a voltage level of the supplyvoltage terminal may be fixed at specific levels or limited withinspecific ranges, but the present invention is not limited thereto.

Note that, if the simulation result obtained from the first timesimulation based on the set of input data (e.g. the input data 120D) isable to reach the predetermined specification, the automated designprocedure may directly enter Step 370 without executing the process ofsubsequent iterative modification. If the simulation result obtainedfrom the first time simulation based on the set of input data (e.g. theinput data 120D) is not able to reach the predetermined specification,the automated design procedure may need to execute the process ofsubsequent iterative modification. Under the condition where circuitarchitecture (e.g. the circuit architecture of the controllableoscillator) to be processed by the automated design procedure is fixed,the automated design procedure may selectively modify at least oneparameter within the parameters of the one or more components accordingto the simulation result.

In addition, the automated design procedure can consider non-idealeffects (e.g. additional parasitic capacitors or parasitic resistors, orcircuit layout mismatch) of the VCO 20 in a physical chip throughmodifying the working flow shown in FIG. 3 (e.g. modifying the programcode 120C), as shown in FIG. 4. In the embodiment shown in FIG. 4, theset of input data may further comprise an initial layout file. Theworking flow shown in FIG. 4 may be obtained by modifying the workingflow shown in FIG. 3, where Step 320 may be replaced with Step 380, andStep 360 may be replaced with Step 390. In Step 380, the automateddesign system 10 may generate an initial layout description fileaccording to the initial circuit description file and the initial layoutfile, and generate the simulation result by performing simulationaccording to the initial layout description file. As the initial layoutdescription file records non-ideal effects generated by the layoutmanner corresponding to the initial layout file, these non-ideal effectscan be considered during simulation. In Step 390, the automated designsystem 10 may modify the initial layout file according to the updatedcircuit description file to generate an updated layout file, and thengenerate an updated layout description file according to the updatedcircuit description file and the updated layout file, and thenre-generate the simulation result by performing simulation according tothe updated layout description file. As the updated layout descriptionfile records non-ideal effects generated by the layout mannercorresponding to the updated layout file, these non-ideal effects can beconsidered during simulation.

To summarize, the automated design method and the automated designsystem of the present invention can perform iterative modification (e.g.modification of transistor sizes) and simulation regarding acontrollable oscillator with fixed architecture, to allow the automateddesign system to make the simulation converge to at least one set ofparameters (e.g. the transistor sizes) under a condition where thenumber of variables is properly controlled, in order to make thecontrollable oscillator be able to meet a target specification. Moreparticularly, after the automated design system 10 receives input data(e.g. the aforementioned initial circuit description file, initiallayout file and/or criteria file), the automated design method of thepresent invention can be automatically executed by the automated designsystem 10, rather than performing parameter modification throughadditional human work. The whole automated design procedure does notneed users to get involved. Thus, the present invention can reduce timefor designing a controllable oscillator without introducing any sideeffect or in a way that is less likely to introduce side effects.

Those skilled in the art will readily observe that numerousmodifications and alterations of the device and method may be made whileretaining the teachings of the invention. Accordingly, the abovedisclosure should be construed as limited only by the metes and boundsof the appended claims.

What is claimed is:
 1. A method for an automated design of acontrollable oscillator, comprising: receiving a set of input datathrough an automated design procedure, wherein the set of input datacomprises an initial circuit description file and a criteria file, andthe initial circuit description file records initial values ofparameters of one or more components within the controllable oscillator;generating a simulation result by performing simulation according to theset of input data through the automated design procedure; and inresponse to the simulation result not reaching a predeterminedspecification described by the criteria file, iteratively modifying atleast one parameter within the parameters of the one or more componentsaccording to the criteria file through the automated design procedure togenerate an updated circuit description file, and performing simulationaccording to the updated circuit description file to re-generate thesimulation result, until the simulation result reaches the predeterminedspecification; wherein in a process of iteratively modifying the atleast one parameter, connection relationships of all components withinthe controllable oscillator are unchanged.
 2. The method of claim 1,wherein the criteria file records one or more limitation conditions ofthe at least one parameter, and the one or more limitation conditionscomprise a parameter range of the at least one parameter.
 3. The methodof claim 2, wherein the parameter range of the at least one parametercomprises a size range of at least one transistor within thecontrollable oscillator.
 4. The method of claim 3, wherein thecontrollable oscillator is a voltage controlled oscillator, the voltagecontrolled oscillator comprises a voltage controlled current source anda buffer circuit coupled to the voltage controlled current source, thebuffer circuit comprises a buffer chain circuit formed by a plurality ofbuffer units connected in series, and at least one of the voltagecontrolled current source and the plurality of buffer units comprisesthe at least one transistor.
 5. The method of claim 1, wherein thepredetermined specification comprises whether a tuning range of anoscillation frequency of the controllable oscillator conforms to apredetermined range value, whether phase noise of the controllableoscillator is less than a predetermined noise value, or whether powerconsumption of the controllable oscillator is less than a predeterminedpower consumption value.
 6. The method of claim 1, wherein thepredetermined specification comprises a voltage range of at least onenode within the controllable oscillator.
 7. The method of claim 6,wherein the controllable oscillator is a voltage controlled oscillator,the voltage controlled oscillator comprises a voltage controlled currentsource and a buffer circuit coupled to the voltage controlled currentsource, the buffer circuit comprises a buffer chain circuit formed by aplurality of buffer units connected in series, the voltage controlledcurrent source is coupled to the buffer circuit via the at least onenode, and the voltage range comprises an upper bound of a voltage levelof the at least one node.
 8. The method of claim 1, wherein the set ofinput data further comprises an initial layout file corresponding to theinitial circuit description file, and the step of generating thesimulation result comprises: generating an initial layout descriptionfile according to the initial circuit description file and the initiallayout file through the automated design procedure; and generating thesimulation result by performing simulation according to the initiallayout description file through the automated design procedure.
 9. Themethod of claim 8, wherein the step of performing simulation accordingto the updated circuit description file to re-generate the simulationresult comprises: modifying the initial layout file according to theupdated circuit description file through the automated design procedureto generate an updated layout file; generating an updated layoutdescription file according to the updated circuit description file andthe updated layout file through the automated design procedure; andperforming simulation according to the updated layout description filethrough the automated design procedure to re-generate the simulationresult.
 10. An automated design system for a controllable oscillator,comprising: a storage device, configured to store a set of input dataand a program code corresponding to an automated design procedure,wherein the set of input data comprises an initial circuit descriptionfile and a criteria file, and the initial circuit description filerecords initial values of parameters of one or more components withinthe controllable oscillator; and a processing circuit, coupled to thestorage device and configured to execute the program code to control theautomatic design system to perform the automated design procedure,wherein: the automated design system performs simulation according tothe set of input data to generate a simulation result; and in responseto the simulation result not reaching a predetermined specificationdescribed by the criteria file, the automated design system iterativelymodifies at least one parameter within the parameters of the one or morecomponents according to the criteria file to generate an updated circuitdescription file, and performs simulation according to the updatedcircuit description file to re-generate the simulation result, until thesimulation result reaches the predetermined specification; wherein in aprocess of iteratively modifying the at least one parameter, connectionrelationships of all components within the controllable oscillator areunchanged.
 11. The automated design system of claim 10, wherein thecriteria file records one or more limitation conditions of the at leastone parameter, and the one or more limitation conditions comprise aparameter range of the at least one parameter.
 12. The automated designsystem of claim 11, wherein the parameter range of the at least oneparameter comprises a size range of at least one transistor within thecontrollable oscillator.
 13. The automated design system of claim 12,wherein the controllable oscillator is a voltage controlled oscillator,the voltage controlled oscillator comprises a voltage controlled currentsource and a buffer circuit coupled to the voltage controlled currentsource, the buffer circuit comprises a buffer chain circuit formed by aplurality of buffer units connected in series, and at least one of thevoltage controlled current source and the plurality of buffer unitscomprises the at least one transistor.
 14. The automated design systemof claim 10, wherein the predetermined specification comprises whether atuning range of an oscillation frequency of the controllable oscillatorconforms to a predetermined range value, whether phase noise of thecontrollable oscillator is less than a predetermined noise value, orwhether power consumption of the controllable oscillator is less than apredetermined power consumption value.
 15. The automated design systemof claim 10, wherein the predetermined specification comprises a voltagerange of at least one node within the controllable oscillator.
 16. Theautomated design system of claim 15, wherein the controllable oscillatoris a voltage controlled oscillator, the voltage controlled oscillatorcomprises a voltage controlled current source and a buffer circuitcoupled to the voltage controlled current source, the buffer circuitcomprises a buffer chain circuit formed by a plurality of buffer unitsconnected in series, the voltage controlled current source is coupled tothe buffer circuit via the at least one node, and the voltage rangecomprises an upper bound of a voltage level of the at least one node.17. The automated design system of claim 10, wherein the set of inputdata further comprises an initial layout file corresponding to theinitial circuit description file; the automated design system generatesan initial layout description file according to the initial circuitdescription file and the initial layout file; and the automated designsystem performs simulation according to the initial layout descriptionfile to generate the simulation result.
 18. The automated design systemof claim 17, wherein the automated design system modifies the initiallayout file according to the updated circuit description file togenerate an updated layout file; the automated design system generatesan updated layout description file according to the updated circuitdescription file and the updated layout file; and the automated designsystem performs simulation according to the updated layout descriptionfile to re-generate the simulation result.
 19. An method for anautomated design of a controllable oscillator, comprising: receiving aset of input data, wherein the set of input data comprises an initialcircuit description file and a criteria file, and the initial circuitdescription file records initial values of parameters of one or morecomponents within the controllable oscillator; generating a simulationresult by performing simulation according to the set of input data; andselectively modifying at least one parameter within the parameters ofthe one or more components according to the simulation result; whereincircuit architecture of the controllable oscillator is unchanged. 20.The method of claim 19, wherein the controllable oscillator is a voltagecontrolled oscillator.
 21. The method of claim 19, wherein the steps ofreceiving the set of input data, generating the simulation result andselectively modifying the at least one parameter within the parametersof the one or more components are executed by an automated designprocedure.
 22. A computer readable medium for an automated design of acontrollable oscillator, wherein the computer readable medium stores aprogram code corresponding to an automated design procedure, and theprogram code is capable of being loaded into a computer in order toexecute following operations: receiving a set of input data, wherein theset of input data comprises an initial circuit description file and acriteria file, and the initial circuit description file records initialvalues of parameters of one or more components within the controllableoscillator; generating a simulation result by performing simulationaccording to the set of input data; and in response to the simulationresult not reaching a predetermined specification described by thecriteria file, iteratively modifying at least one parameter within theparameters of the one or more components according to the criteria fileto generate an updated circuit description file, and performingsimulation according to the updated circuit description file tore-generate the simulation result, until the simulation result reachesthe predetermined specification; wherein in a process of iterativelymodifying the at least one parameter, connection relationships of allcomponents within the controllable oscillator are unchanged.
 23. Thecomputer readable medium of claim 22, wherein the criteria file recordsone or more limitation conditions of the at least one parameter, and theone or more limitation conditions comprise a parameter range of the atleast one parameter.
 24. The computer readable medium of claim 23,wherein the parameter range of the at least one parameter comprises asize range of at least one transistor within the controllableoscillator.
 25. The computer readable medium of claim 24, wherein thecontrollable oscillator is a voltage controlled oscillator, the voltagecontrolled oscillator comprises a voltage controlled current source anda buffer circuit coupled to the voltage controlled current source, thebuffer circuit comprises a buffer chain circuit formed by a plurality ofbuffer units connected in series, and at least one of the voltagecontrolled current source and the plurality of buffer units comprisesthe at least one transistor.
 26. The computer readable medium of claim22, wherein the predetermined specification comprises whether a tuningrange of an oscillation frequency of the controllable oscillatorconforms to a predetermined range value, whether phase noise of thecontrollable oscillator is less than a predetermined noise value, orwhether power consumption of the controllable oscillator is less than apredetermined power consumption value.
 27. The computer readable mediumof claim 22, wherein the predetermined specification comprises a voltagerange of at least one node within the controllable oscillator.
 28. Thecomputer readable medium of claim 27, wherein the controllableoscillator is a voltage controlled oscillator, the voltage controlledoscillator comprises a voltage controlled current source and a buffercircuit coupled to the voltage controlled current source, the buffercircuit comprises a buffer chain circuit formed by a plurality of bufferunits connected in series, the voltage controlled current source iscoupled to the buffer circuit via the at least one node, and the voltagerange comprises an upper bound of a voltage level of the at least onenode.
 29. The computer readable medium of claim 22, wherein the set ofinput data further comprises an initial layout file corresponding to theinitial circuit description file, and the operation of generating thesimulation result comprises: generating an initial layout descriptionfile according to the initial circuit description file and the initiallayout file through the automated design procedure; and performingsimulation according to the initial layout description file through theautomated design procedure to generate the simulation result.
 30. Thecomputer readable medium of claim 29, wherein the operation ofperforming simulation according to the updated circuit description fileto re-generate the simulation result comprises: modifying the initiallayout file according to the updated circuit description file throughthe automated design procedure to generate an updated layout file;generating an updated layout description file according to the updatedcircuit description file and the updated layout file through theautomated design procedure; and performing simulation according to theupdated layout description file through the automated design procedureto re-generate the simulation result.